The prior art literature is replete with a wide variety of vertical seismic profiling information. An excellent bibliography is contained at the back of the book entitled "Vertical Seismic Profiling"; part A principles; Bob A. Hardage; HANDBOOK OF GEOPHYSICAL EXPLORATION, Section I Seismic Exploration; Claus Helbig and Sven Treitel (Editors); Geophysical Press Limited, Westcombe House, 56-58 Whitcomb Street, (multiple volumes) London WC2H7DR, United Kingdom, 1983. As noted in that book, the Russians have used vertical seismic profiling technology for at least the past twenty-five years and it has become increasingly important in exploration techniques in the free world, particularly, in the United States. That bibliography, or references beginning at page 421, contains records of a wide variety of different approaches, including theoretical treatises and practical installations. As noted in the preface to that book, the inventor of this invention is given credit for significant contributions in the western world, or free world.
The closest prior art of which I am aware is a cable developed by the Kerite Company. Various production committees have suggested that cable would be useful for lowering into the well downhole pumps or the like. This would obviate the requirement for separate load-bearing lineal means, such as tubing, to support the pump and facilitate installation and even removal for repair of downhole pumps or the like.
One of the problems that has been concomitant with vertical seismic profiling in the past has been the unduly long time required to put in multi-level geophone tool into a well. This is particularly important where an offshore rig is standing by while the vertical seismic profiling is being performed at a well location. There has been a longstanding need that the prior art has not yet satisfied for a multi-level geophone sonde installation in which the tool could be emplaced and the vertical seismic profile run within a time period of only five to six hours, instead of having to have at least a full day of rig down time waiting for a vertical seismic profile log to be run.